Prick punching fixtures for wave guide flange



March` 18, 1958 B. C. CALHOUN, JR

PRICK PUNCHING FIXTURES FOR WAVE GUIDE FLANGE Filed Dec. 5l, 1952 INVENTOR` wim ff/bzw@ J BY fr /n I 2 A1 1 ORNEY PRICK PUNCHING FIXTURES FOR WAVE GUIDE FLANGE Burton C. Calhoun, Jr., Winston-Salem, N. C., assigner to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application December 31, 1952, Serial No. 328,891

2 Claims. (Cl. 78-1) This invention relates to work fabrication apparatus and more particularly to a prick punching fixture for producing spaced upsets or craters -of predetermined dimensions upon the inner surface of a wave guide flange.

In joining together precision dimensioned members such as wave guide tubing and wave guide flanges, wherein an inner member is slidably inserted into a slightly larger outer member, it is necessary to maintain a uniform clearance between the outer surface of the inner member and the inner surface of the outer member for subsequent operations such as soldering or brazing. y

Accordingly, it is an object of this invention to provide apparatus for concentrically positioning two members whereby the inner member may be quickly, automatically and accurately positioned Within the outer member with a fixed clearance between them.

In one embodiment of the present invention, particularly designed for centering rectangular wave guide tubing within a wave guide flange of similar contour, prick punches, slidably movable within a rectangular fixture block, are caused, by means of impact camming members or rods, to penetrate for a predetermined distance into the inner wall of a metallic wave guide flange to cause the metal of the wall of the ange to flow outwardly about the punches thereby creating protruding crater-like upsets upon the inner flange wall surface, the height of the upsets being dependent upon the controlled distance of penetration of the prick punches.

Gther features and advantages of the invention will become apparent in the following detailed description, when taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a perspective vieW of the assembled prick punching fixture embodying the present invention;

Fig. 2 is a vertical cross section of this xture taken on line 2--2 of Fig. l;

Fig. 3 is a vertical cross section of the fixture taken on line 3 3 of Fig. l and showing the fixture in operative position inside a wave guide flange; and

Fig. 4 is a vertical cross section of the rectangular wave guide tubing and flange showing, in enlargement, the spacing upsets or craters upon the flange wall to provide a predetermined clearance between the inner walls of the flange and the outer walls of the tubing.

Referring now t-o the drawings, wherein like reference numerals designate the same elements through the several views, and more particularly to Figs. l and 2, a plurality of prick punch holders l are inserted with a working t into laterally extending passages 12 in a fixture block 13. These prick punch holders are provided with forty-five degree conical cam portions 14 and cylindrical portions 15 having vertical apertures 16. The cylindrical portions of the prick punch holders terminate in flat circular surfaces 17 into which exten-d horizontal apertures 18. Pieces of piano wire 19 are inserted through a plurality of apertures 20 in the fixture block and are drive fitted into the apertures 16 in the prick punch holders lt? so that the ends of the wires 19 in the apertures States Patent 0 ICC 16 project therefrom and extend into the apertures 20 of slightly larger diameter so as to be capable of limited lateral resilient motion therein. Prick punches 22 are drive fitted into the apertures 18 in the prick punch holders 1t) until the rear ends of the prick punches abut the movable wires 19. In the normal operative position of the fixture the points of the prick punches 22 are flush with the surface of the inner wall of the wave guide flange 23 as shown in Fig. 3.

Cylindrical impact camming members or rods 24 are slidably movable within vertically extending passages 2S in the fixture block 13. The lower end of each impact actuating member 24 is provided with a forty-five degree conical surface 26 which, upon inward motion thereof, engages the similarly shaped portions 14 of the prick punch holders with a cam-like action thereby forcing the prick punches 22 for a 'predetermined distance into the wall of the Wave guide flange 23 to form upsets or craters 27 upon the inner wall of the flange. The spaced craters so produced provide a uniform clearance between the flange 23 and the wave guide tubing 28 when these parts are assembled as shown in Fig. 4. Any suitable means such as a hammer or a mechanically operated ram 21 may be used to deliver the impact to the impact members, which, as shown in Fig. l, may be used singly or actuated simultaneously in groups of two or more. The maximum distance of travel of the impact camming member 24 is limited by an adjustable collar 29 which is fixed thereon by means of set screws 30 threaded into apertures 32 in the collar.

In operation, the prick punching fixture of Fig. l is inserted (Fig. 3) into the wave guide flange 23 to be provided with the desired spaced crater-like upsets 27. The depth of penetration of the prick punches 22 having been previously determined by the positioning of collars 29 by means of set screws 30, the impact camming members or rods 24 are then inserted into the passages 25 in the block 13 and an impact delivered thereto by a suitable means such as a mechanically operated ram 21 as shown in Fig. l. This impact actuates the associated conical portions 14 of the prick punch holders 10 by va camming action, whereupon prick punches 22 are forced in a lateral direction into the wall of the flange 23 to produce the crater-like upsets 27 as shown in Fig. 4. Upon impact, the spring wires 19 are distorted, resulting in a tensional force to return the prick punch holders to their normally retracted positions after temination of the impact force.

With the Wave guide tubing and the flange assembled as shown in Fig. 4, the spaced crater-like upsets 27 provide a fixed and uniform spacing between the inner walls of the flange and the outer walls -of the tubing to receive a soldering or a brazing material for securing the flange and the tubing together.

Although the above description refers specifically to apparatus for producing upsets in a rectangular metallic wave guide flange, it is obvious that any hollow article affording access from the exterior may be similarly worked upon to produce spacing craters of a desired height, and it will be understood that the described embodiment is merely illustrative of the invention and that various modifications can be made without departing from the spirit or scope of the invention.

What is claimed is:

l. In a prick punching fixture for use in producing upsets of a predetermined height upon the inner surface of a tubular wave guide: a fixture block slidably insertable within the wave guide, said block having a plurality of laterally extending passages and interconnecting therewith at right angles thereto a plurality of vertically extending passages extending from the top surface of the block, said block further provided with a plurality of apertures` extending transversely therethrough and interconnecting with the laterally `extending passages; a plurality of prick punching means slidably movable within the laterally extending passages; a metallic resilient member extending transversely through each prick punching means; the ends of said resilient members beingl loosely held within the transverse apertures which interconnect with the laterally extending passages, said resilient members serving to maintain the prick punching means within the fixture block and to return said punching means to the normally retractedposition after impact; and an impact member slidably movable within the vertically extending passages and operatively engageable with the prick punching means to `produce upsets on the inner surface ofthe tubular wave guide.

2. In a` prick punching fixture for use in producing crater-like upsets of a predetermined height upon the in nersurface of `a rectangular wave guide flange: a fixture block slidably insel-table withinthe flange and having a plurality of `horizontal cylindrical-passages extending perpendicularly inward from the lateral surfaces of the block', said block also havinga plurality 'of vertical cylindrical passages extendingperpendicularly downwardfrom the top surface thereof and interconnecting with one or more of the horizontal passages and a plurality of lvertical apertures extending perpendicularly from` the top and' bottom surfaces of theblock, each of Vsaid'vertical aper tures interconnecting withV one horizontal-passage; a pluralityY of prick punch holdersslidably 4movable within the horizontal passages, each of said holders' comprising a cylindrical portion terminating ina flat circular face andy a forty-vedegree conical portion projecting info that portion of `the horizontalpassage which connects with the vertical passage, each of the said prick punch holders having one or more apertures extending longitudinally thereof from the flat circular faceV and interconnecting at right angles with a passage extending transversely through the cylindrical portion of each prick punch holder; means 4F for pricking the inner surface of the wave guide ange comprising one or more prick punches drive fitted into the longitudinal apertures in the prick punch holders, projecting points of sadprick punches being ush with the inner wall surface of the wave guide when the fixture is in operative position, a spring wire drive fitted into the passage extending transversely through the cylindrical portion ofrpeach prick punch holder, said spring wires being capable of limited lateral motion within the vertical `apertures which interconnect with the lateral passages accommodating the prick punch holders whereby the prick punch holders are held within the fixture block and returned to the normally retracted position after impact; cylindrical impact members each provided at the lower end thereof with a forty-five degree conical surface which cooperates with the similar conical surfaces of the prick punch holders; a circular collar slidably adjustable upon each impact member; means for locking the collar to the impact member to limit the movement of said impact members; and meansA for actuating the impact members.`

References Cited in the file of this patent UNITED STATES PATENTS 

